1. Clinical Overview
A combined live attenuated viral vaccine for active immunization against measles and rubella. It contains the Edmonston-Zagreb measles virus strain and the RA 27/3 rubella virus strain, each with a potency of not less than 1000 CCID50 (Cell Culture Infective Dose 50) per 0.5 ml dose. It is a critical component of India's Universal Immunization Programme (UIP) and is administered as part of the MR (Measles-Rubella) campaign to achieve elimination targets.
| Onset | Duration | Bioavailability |
|---|---|---|
| Protective antibody levels typically develop within 2-3 weeks post-vaccination. | Long-lasting immunity; seropositivity for measles persists for at least 15-20 years, and for rubella, it is considered lifelong in >95% of vaccinated individuals. | Not applicable (Parenteral administration). |
2. Mechanism of Action
Contains live, attenuated strains of measles and rubella viruses. Following subcutaneous administration, the attenuated viruses replicate locally and in regional lymph nodes, stimulating a protective immune response (both humoral and cell-mediated) without causing clinical disease in immunocompetent individuals. This mimics natural infection and leads to the production of specific neutralizing antibodies and memory B and T cells.
3. Indications & Uses
- Active immunization against measles (Rubeola) in children from 9 months to 15 years of age.
- Active immunization against rubella (German Measles) in children from 9 months to 15 years of age.
- As part of the National MR Vaccination Campaign in India for catch-up vaccination.
4. Dosage & Administration
Adult Dosage: Not routinely recommended for primary immunization. For susceptible adults (especially women of childbearing age), a single 0.5 ml dose. MMR vaccine is preferred.
Administration: For subcutaneous use only. Reconstitute the lyophilized vaccine with the entire content of the supplied diluent. Shake well until a clear, yellow to red-hued solution is obtained. Use immediately (within 4-6 hours if stored at 2-8°C post-reconstitution). Administer in the upper arm's outer aspect. Do not administer intravenously or intradermally.
5. Side Effects
Common side effects may include:
- Pain, redness, or swelling at the injection site.
- Low-grade fever (usually 6-12 days post-vaccination).
- Mild rash (non-infectious, appearing 7-10 days after vaccination).
- Irritability, malaise.
6. Drug Interactions
| Drug | Effect | Severity |
|---|---|---|
| Immunosuppressants (Corticosteroids, Chemotherapy, Azathioprine, etc.) | Diminished immune response to vaccine; may lead to vaccine failure or increased risk of adverse events. | Major |
| Immunoglobulins or Blood Products | Antibodies in these products may neutralize the vaccine virus, leading to suboptimal immune response. Vaccination should be deferred for 3-11 months depending on the product dose. | Major |
| Other Live Vaccines (e.g., OPV, Varicella, Yellow Fever) | If not administered simultaneously, should be spaced at least 4 weeks apart to avoid interference. | Moderate |
| Tuberculin Skin Test (PPD) | May cause false-negative results. Administer PPD either before, simultaneously with, or at least 4-6 weeks after MR vaccine. | Moderate |
7. Patient Counselling
- Do ensure your child receives both doses as per the national schedule.
- Do inform the doctor about any history of allergies, immunodeficiency, or recent illness.
- Do apply a cold compress if there is local pain or swelling.
- Do monitor for fever; paracetamol can be given if fever is distressing (but not routinely prophylactically).
- Don't give the vaccine if the child has a high fever or severe illness.
- Don't rub the injection site vigorously.
- Don't get pregnant for at least 1 month after vaccination (for women of childbearing age).
8. Toxicology & Storage
Overdose: Unlikely due to fixed single-dose vial. Accidental repeat dosing may increase the frequency of known adverse effects (fever, rash).
Storage: Store frozen at -20°C to +8°C for long-term storage (as per manufacturer). In the vaccine cold chain, store at +2°C to +8°C. Protect from light. The diluent can be stored separately at room temperature. Do not freeze the diluent. After reconstitution, use immediately or store at 2-8°C and discard if not used within 4-6 hours.